Technical Field
Embodiments of the present disclosure relate generally to mechanical engineering and in particular to method, system, apparatus and device for directional flow control of fluids and gases.
Related Art
A valve is a device which regulates, directs and controls the flow of a fluid. Valves are often used to control the pressure, flow rate and flow direction of the fluid/gases (hereafter referred to as “fluids” in general). The fluid may include gases, air, liquids, fluidized solids, or slurries. In general, the movement of fluid is from a higher pressure area to a lower pressure area.
Generally fluid is pressurized using a pump and this pressurized fluid is used to control actuator in which a pressurized fluid causes linear movement of a piston. The pressure, quantity of fluid is generally determined based on the size of the actuator piston and the force needed to get a specific work done by piston. Valves are used to control the direction of the movement of the piston in the actuator. A spindle in the valve operates to control the flow of the fluid. When the spindle is at a first position, the pressurized fluid in made to flow in one direction. When the spindle is moved to the second position, the fluid is made to flow in the other direction. Thus, the valve is used to control the movement of the piston back and forth. Hence a small force exerted on the spindle of the valve controls the large force applied to the actuator piston. In one prior technique, a spool valve is used to control the actuator piston movement.
FIG. 1 is a conventional system shown comprising actuator 105, pump 110, tank 120 and spool valve 115 with connecting pipes 125,130,135,140,145,150. Each element is described below in further detail.
The pipes 150 and 145 are connected respectively to the tank outlet 111 and 112 to guide the fluids into the tank/reservoir. The pipe 125 is connected between the tank and inlet to the pump 110. The pump sucks the fluid through the pipe 125. The pipe 130 is connected between the pump outlet and pressure inlet (P) 113. The pressurized fluid (by the pump) is forced through the pipe 130 to the pressure inlet (P) 113 of the valve. The pipe 135 is connected between the port A of the valve and the piston rod side space of the cylinder. The pipe 140 is connected between the port B and the flat side (of the piston) space of the cylinder. The tank 120 stores the fluid, liquids, fluidized solids etc. The tank 120 represents atmosphere in the case of air, or gases.
The spool valve 115 is shown comprising spindle 118, tank inlets (T) 111 and 112, pressure port (P) 113, port A 116 and port B 117. When the spindle 118 is in first position (as shown in FIG. 1) the pressure port (P) 113 is connected to the port A 116 and tank inlet 112 is connected to port B 117. When the spindle 118 is in second position (moved upwards from the position shown in FIG. 1) the pressure inlet (P) 113 is connected to port B 117 and the tank inlet is connected to the port A 116. The actuator is shown with an actuator cylinder 155, actuator piston with rod 160, piston side space 165, and flat side space 157.
The manner in which the actuator piston is actuated back and forth by the spindle in the conventional system is described below.
FIG. 1 illustrates the position of the spindle when it is moved down (first position as shown in FIG. 1). Accordingly, the pressure port (P) 113 is connected to the port A 116 and the tank outlet is connected to port B 117. Thus, the pressurized fluid is forced into the piston rod side space forcing the piston downwards. The downward movement of the piston exits the fluid in the flat side space, through the pipe 140 flown into the tank through port B 117 of the valve, the tank inlet 112 and pipe 150.
Similarly, when the spindle is moved upwards, (not shown) the pressure port (P) 113 is connected to port B 117 and the tank inlet is 111 is connected to port A 116. Thus, the pressurized fluid enters the flat side space of the cylinder through pipe 140 forcing the piston upwards. The upward movement of the piston exits the fluid in the piston rod side space through the pipe 135. This forced fluid reaches the tank through the port A, tank inlet 111 and pipe 150. Thus, when the spindle is moved upwards, the piston is also moved upwards by the pressurized fluid. The actuator rod piston 160 is moved up and down (or linearly back and forth) within the actuator cylinder 155 when the spindle 118 is moved up and down. The piston rod 160 is coupled to the desired load to achieve the desired work done.